[R] Convert color hex code to color names

[Boris Steipe]

To add slightly to that:

What you want to do is write a function that returns the named color that has the smallest difference to your input hex-triplet. But note that color difference is a large topic. Assuming you want to minimize *perceptual* differences, you want to calculate your differences in Lab color space. The function convertColor() has the option to convert hex to Lab. Example:
convertColor(t(col2rgb("thistle")), from="sRGB", to="Lab", scale.in=255)

Within Lab space, you can take the Euclidian distance.

That all said, I can't imagine why one would want to do this in the first place - color triplets are much more convenient than label strings :-)


B.




On Apr 13, 2015, at 11:45 AM, Thierry Onkelinx <thierry.onkelinx at inbo.be> wrote:

> A combination of rgb(), col2rgb() and colors() can gives hex values for the
> named colors.
> 
> ir. Thierry Onkelinx
> Instituut voor natuur- en bosonderzoek / Research Institute for Nature and
> Forest
> team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
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> 
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> 
> 2015-04-13 17:28 GMT+02:00 Alejo C.S. <alej.c.s at gmail.com>:
> 
>> Hi all, I want to convert the output of:
>> 
>>> rainbow(6)
>> 
>>> [1] "#FF0000FF" "#FFFF00FF" "#00FF00FF" "#00FFFFFF" "#0000FFFF"
>> "#FF00FFFF"
>> 
>> To a vector of color names. Any tip?
>> 
>> 
>> Thanks in advance
>> 
>> C.
>> 
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